RFR: 8309460: JScrollBar leaves behind clutter for non-integer UI scales

[Prasanta Sadhukhan]

On Thu, 18 Jan 2024 11:09:12 GMT, Prasanta Sadhukhan <psadhukhan at openjdk.org> wrote:

> Lines  are left behind when moving the scrollbar in the positive direction. but are cleaned up on mouse release. 
> Additonally, with right arrow clicks too, the lines are left behind.
> Seems like for mouseDragged and scrollByUnit, the dirty region of the scrollbar is not repainted leading to artifacts
> which is being done in this fix..

Looks to be related to 
8032219: [macosx] Scrollbars looks bad under retina 
which changes the way scrollbar is drawn for Metal and Motif L&F by using fillRect instead of drawLine

and the current issue also happens for Metal and Motif L&F
but not for say, Windows and Nimbus L&F

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PR Comment: https://git.openjdk.org/jdk/pull/17484#issuecomment-1905274881